The present invention relates to an in-vehicle device which performs wireless communication with a plurality of mobile terminal devices in a vehicle and a communication control method of wireless communication.
Recently, car navigation systems have come into wide spread use. Generally, an in-vehicle device which is capable of allowing users to listen to music and watch movies and displaying navigation information is mounted in a vehicle. Such an in-vehicle devices can communicate with the mobile terminal devices such as mobile phones and Personal Digital Assistants (PDAs) carried on occupants and transmit and receive data to an from the mobile terminal devices.
As a communication method for short-range wireless communication between communicable devices, there are wireless communication standards, for example, Bluetooth (registered trademark). Bluetooth is the wireless communication standard using a frequency band of 2.4 GHz, by which wireless communication within a several-meter radius is possible.
However, in the wireless communication between the in-vehicle device and the mobile terminal devices, Bluetooth allows the in-vehicle device and the mobile terminal devices to have a one-to-many corresponding relation. In this relation, the mobile terminal devices can identify the in-vehicle device, but the in-vehicle device cannot identify the mobile terminal devices. For this reason, a problem of crosstalk occurs between a plurality of mobile terminal devices. For example, with a hands-free function of the mobile terminal device, there is the inconvenience that communication may be performed through another mobile terminal device.
Thus, a related art sets a wireless communication device and each mobile terminal device to have one-to-one corresponding relation in the wireless communication such as Bluetooth. In this relation, the wireless communication device can perform wireless communication with each mobile terminal device by individually controlling each device so as to prevent crosstalk, and the wireless communication device can be shared by each mobile terminal device. Accordingly, it is possible to secure the confidentiality of wireless communication between the wireless communication device and each mobile terminal device by preventing crosstalk (see, Japanese Patent No. 3711394, Japanese Patent Publication No. 2002-51058A, Japanese Patent Publication No. 2001-277962A, Japanese Patent Publication No. 2003-312391A, and Japanese Patent Publication No. 2007-116254A).
As described above, the in-vehicle device (the wireless communication device) as a hardware can be shared by a plurality of mobile terminal devices. However, in the current situation where various kinds of services are available in the mobile terminal devices, it is difficult to share the services among the plurality of mobile terminal devices while securing the confidentiality of wireless communication.
For this reason, it is not possible to distinguish services which may be shared with the other mobile terminal devices from services which are not intended for sharing, and even a service not intended for sharing may be shared. For example, in a hands-free service, there is a problem that even when a user does not want to allow fellow passengers to hear the content of phone communication, the fellow passengers may hear the content of phone communication.